Replacing Pressure Washer Pump Parts

If the pump in your pressure washer has developed a fault, you do not need to go and buy a new pressure washer. Instead, repair the fault by following the advice in this video.For information on how to repair Pressure washer problems see our other articles.

Tools that you will need

Video Transcript: Replacing Pressure Washer Pump Parts

Welcome to BuySpares, in this video we will be showing you how to repair a pump fault on a Kärcher pressure washer pump.


Fault finding your pressure washer fault or how to fit an electrical part are covered in our other videos.

Remove the covers to access the motor assembly.

Ensure the motor is free from any fixings or brackets and lift it from the case.

Take care when dismantling the pump, the gearbox between the motor and the pump is full of oil. Unless you intend replacing this avoid letting it spill by ensuring the pump is upright as you remove the screws.

Rotate until the switch is at the top, and carefully lift off the pump assembly and disconnect any wires to the pump motor. You can now remove these screws to remove the cylinder head.

Once the cylinder head is removed you can replace the grooved seals on the pistons, or replace the form seal, or valve sets, or change the cylinder head itself. When refitting seals it is important to lightly lubricate them with the special grease supplied by Kärcher – if you have lost oil from the gearbox top it up before reassembling.

Check all parts are clean and free from contamination as you reassemble the cylinder head.

Refit the switch on to the actuator piston and click in place.

After repair refit the motor and any fixing brackets and screws to the lower case.

Ensure all cables and the detergent hose are connected and dressed correctly in the case.

Turn the switch and the knob to the off position and check they engage correctly as the upper case is fitted, refit all screws and any additional parts.

For all the spares you need visit the BuySpares website.

When using any electrical tools in the garden always use a RCD safety device

* All information provided is a guide only. BuySpares accepts no liability for any problems occurred while attempting any advice shown. If in any doubt contact a qualified repair service.

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